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(No Model.) v 4 Sheet s-Sh eet 1,. A. F. BROWN.

UNDBRFEED STOKER.

bro/570,978.

Patented Nov. 10, 1896.

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(No ModeL) 4 Sheets-Sheet 2. A. F. BROWN.

UNDERFEED STOKER.

Patented NOV. 10, 1896.-

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%%M. 9 Ohm '4 Sheqts-Sheet 3.

(No Model.)

A. F. BROWN.

UNDERFEED STOKER. I 4 No. 570,978. Patented Nov. 10. 1896.

m WWW m (No Model.) 4 Sheets8heet 4.

- A. F. BROWN.

UNDERFEED STOKER.

Patented Nov. 10,- 1896.

44, flOMM forth in the claims. s.

' bodying my invention.

the device for c'ounteracting'the back pres- 'sure in the conduit.

the outside of the furnace wall or front, and

'citizen of the United ton, in the county of Montgomery and State of Ohio, have invented ful Improvements in Underfeed Stickers for 'u-nderfeed stokers for steam-boilers; and it sectional View 20 tion, and Fig. 5 a sectional elevation, of a pore 'ing and feeding mechanism.

below the hopper b which are located conveyor-flights b form- .conveyer which is within the chamber 12 at UNITED STATES PATE T OFFICE- STOKER COMPANY,

oi THE AMERICAN or SAME PLACE.

UNDERFEED STO KER.

, SPECIFICATION formingpart of Letters Patent No. 570,978, dated November 10, 1896.

' Application filed 0mm 28, 1895. 1

1'0 all 1071,0722, 1115 may concern-.- Be it known that I, ARTHUR F. BROWN, a

States, residing at Daycertai-n new and use- Steam-Boilers, of which the following is a specification.

My invention relates to improvements in consists in the constructions and combinations of parts hereinafter described, and set In the accompanying drawings, Figure 1 is a' longitudinal sectional view of a device em- Fig. 1 is a detail of Fig. 2 is a transverse of the same; Fig. 3 is a plan I viewof a portion of the same with some of tl1e.parts removed. Fig. 4 is an end elevationof the same, showingthe driving mechanism. Figs. 6, 7, and 8 are details of .the same, showing devices for adjusting the driv- Like parts are represented by similar letters of reference in the several views.

I11 the said drawings, a-represents a furnace of any suitable construction, and a the the same. b is a magazine into which the fuel is fed, and which is located in the ash-pit or below the furnace, so that the may be provided at each side of the magazine with the usual grate-bars a if desired.

The main body of the magazine is substantially U shape, as shownin Fig. '2, and is provided at the bottom with a chamber b, which forms a substantial continuation of a pipe oi conduit b which leads therefrom'to is there provided with a hopper b J'Extending through the chamber bflthe conduit b and is a rotating shaft 1), on

ing a screw conveyer. Thatportion of the the bottom of the magazine is preferably re.-

after, it

magazine. 7

Openings 0' inthe tops of theair trunks or I 'conduitscesta pairs or otherwise. the magazine are also preferably provided I with removable blocks 1)",

Serial No. 567,129. (No model.)

duce a distribution of the fuel, as-hereinafter more fully specified, the construction shown in the drawings in Figs. 1 and 3 illustrating conveyer-flightsb of reduced diameter.

The fuel 'is fed into the hopper b 'and means are provided for rotating the shaft 0-, so that the fuel-will be conveyed from the hopper through. the conduit'into the chamber, from by reason of the constructions herein whence, described and more fully explained hereinwill be caused to raise vertically into the magazine and spread over the bottom of the furnace.

The magazine is provided at each side and along the top witha series of twyer-blocks b, which have at the top suitable dischargeopenings (2 which discharge lateralfyinto the upper portion of the magazine. blocks Z1 are each formed in cross-section substantiallyL-shapedand are adapted to partially surround an air trunkor conduit 0, one of which is formed on each side of the lish a communication between the air-trunkls and the respective twyerblocks, the twyer-blocks'being hollow on their under sides,*so as to form an air-chamber which extends substantially around the top and exposed side of said air-trunk. The twyer blocks are also preferably formed slightly curved or at an angle at the top, so asto leave a space c on the top of thesame, which may be filled protecting substance. The 'twyer-b1ocks bare separable and removable, so that-they may be readily removed or replaced for rei he respective ends of with. an air-chamber b", which may or may not communicate with the air-trunk, these blocks being adapted to form a protection'for the ends of I the magazine and may be replaced when warped or damaged by heat. I

' The respectiveair-trunks c are connected by branch pipes 0 tea main pipe or'conduit c which is preferably arranged beneath "the These twyerpitch or diameter, so as to with fire-clay or other which are formed floor of the ash-pit and leads to-any suitable source of air supply, such as a fan or pressure-blower. 1

The outer end of thefuel-cond-uitb as well as the hopper, is preferably supported by a head b through which the end of the con-.

veyer-shaft b? is adaptedto extend. On this shaft is mounted a ratchet-wheel d, on each side of which is journaled an arm d, the op posite ends of which are pivoted toa pitman.

and adaptedfito engage in the ratchet-teeth and prevent the backward rotation of said ratchet-wheel. By this construction the pawl (Z is adapted at each revolution of the crank shaft to travel over a definite number of teeth of the ratchet-wheel, and, if unobstructed, would turn the conveyer-shaft a definite distance at each stroke. To provide for varying the movement of the conveyer-shaft, and thus the amount of feed, I employ a movable track 11 which is secured to an adjustable arm d pivoted at the center of the shaft 1), so as to be moved around the ratchet-wheel. This track (Z- issufficiently long so that when moved under the pawl d the pawl-will complete itsentire stroke on said track. By shifting the track more or less out of the path of the pawl, the pawl will be caused to engage the teeth for agreater or less portion of its stroke, and thus vary the movenrent'imparted at each stroke to the conveyer-shaft and conveyer. A notched segment (1 isprovided adjacent to the arm dia suitable holding-pawl (1 being provided on said lever to engage in the notched segment and hold said lever in diiferent positions of adjustment.

As before stated, the fuel is fed intothe hopper b and as the conveyeris revolved itis carried through the conduit into the chamberin the bottomof the magazine. To provide for distributing the coal or other fuel, the conveyer-flight-s are reduced in size in the magazine, so that only a portion of the fuel fed to the chamber 1) will be carried longitudinally therein. This will cause the coal to rise in themagazine and become distributed evenly in the length thereof. The front'end of the magazine where the conduit joins the same is cut out at an angle, as shown at b, forming an angularly-arrange'd passage-way from the top of the conduit upwardly into the magazine. This angularly-arranged passage begins at or near the point where the conveyorflights arereduccd or changed in their carrying capacity, so that a portion of the fuel which is brought to this point will rise in said passage from the fact that more fueiis brought to this point than is carried into the magazine longitudinally. .Dhis angular passage permits the fuel to end of the magazine. It may 'be' found desirable in some cases to place one or more conyeyer-flights on the shaft in areverse direction, as shown at b, to assist in holding back the fuel, and thus causing it to rise vertically by the pressure of thefresh fuel againstthe same.

To provide for adj usting the conveyer lonbe delivered at tires-rent gitudinally and thus regulate the distribution of the fuel longitudinally in the magazine, I preferably support the front end of the shaft in a screw-threadedsleevje e, which is screwed into a boss 6 on a yoke e, which 01w is connected to the head bl. The sleeve; e is bored out to receive the end I) of the shaft, which is shouldered down atthis point to enter said sleeve. The front end of the sleevee is providedwith an enlarged cylindrical portione which is. cupped out to re ceive bearing-plates e e, which are each formed with circular grooves on the adjacent faces adapted to receive antifriction-balls e, which are placed between the plates. One of these plates is adapted to turn with the shaft 1), the shoulder of which rests against said plate, the other plate, e being adapted to rest in the cylindrical portion of the sleeve. 1 The end thrust is thus'receiv'edbn the ball-- bearin gs formed in said sleeve. The opposite end of the sleeve where it extends through the boss egis formed square in cross-section,=. 1oo

as shown at e. and adapted to receive a wrench by means of whichit may be adjusted back and forth in the bearing-boss,' and thus adjust the conveyer-shaft longitudinally through the conduit and the magazine. For the purposes of this adjustment the ratchet-wheel d is constructed with asquare opening, which fits on, the square portion of the shaft 11 and the pivoted arms d are journaled on the hubs of said wheel on opposite sides thereof.- Projecting lugs e on the yoke e prevent lateral movement of said ratchet-wheel as the shaft is adjusted back and forth. The bearing-plates e e in. the cylindrical portion a of the screw-threaded sleeve 6 are held in position by suitable retaining-clips e5, which are bolted or otherwise secured to the cylindrical casing and project inwardly, so as to engage and hold the plate e 'In stokers of this class. it sometimes happens under certain conditions and with certain kinds of fuel that the air? introduced into the twycrs will not find ready escape through the burning fuel, and a slight pressure will accumulate in the magazine suflicient to cause a portion of the smoke and gases to find their way back through the conveyer and into the hopper Z1 To obviate this, I provide means for counteracting this pressure in theconduit, and thus prevent the escape of air or gas through this passage. This is preferably accomplished by introducing a jet of air from the main trunk or any other portion of the air supply into the conduit, preferably at an anglein the direction in which the fuel moves. I

This -I have shown in FigsIJ and 1, in which a small pipe a is introduced atan angle into the top of the conduit b In case the airchamber b is connectedwith the air-trunk thenthepiper may be connected directly with this air space and receive its supply therefrom, as shown in the drawin gs. To prevent the choking of the pipe by the inward lylar concave pocket into the top of which the pipe 0 is made to enter, so that an airpassing fuel in the conduit, I preferably construct the conduit at this point with a circuspace is formed at this point which will prevent the choking ofthe pipe by the fuel. This air-space being circular and concavc,any

fuel which should be crowded into the same through any obstruction in the feed would iind easy passage from said pocket as soon as,

the irregularities of the feed were overcome. Having thus described my invention,- 4 I claim 1. In an under-feed stoker, a fuel-hopper, a

' horizontal conduit leading from said hopper,

and a feeding chamber or magazine having a curved bottom forming a substantial continuation of said conduit and provided with inclined sides and of gt-substantially uniform width, ajscrew conveye'r. extending from said hopper through said conduit and through the bottom portion of said magazine, and an angularly-arranged passage formed in said conduit and extending upwardlytherefrom so as tocommufiicate with the front of said magazine above the mouth of said stantially as'spe'cificd; v

- 2. In an underfeed stoker, a feed-magazine having air-trunks formed on each side thereof and removable twyer-blocks with openings at the top, said twyer-blocks being cored out and form ed substantially L-shaped in cross-section so as to extend over and protect the inner side and top of said air-trunks, substantially as specified. j

The combination with a feedin g chamber or magazine having the air-trunkson the sides thereof, and devices for feeding the fuel into, the bottom of said magazine, of removable plates surrounding said magazine at or near the top, said plates being formed in the'nature of twyer-blocks and adapted to extend over the top and inner sides of saidair-truuks,

substantially as specified. I g

lh'lhecombination with the fuel-hopper and a conduit, a conveyer extending through said conduit, a ratchet-wheel on the conveyer-shaft and a bearing-support for said shaft, a hand-lever journaled concentric with said shaft. and carrying at one end a circular track adaptedt-o project over said ratchetwheel, and a stationary notched segment connected to said bearing-support, and a holding-pawl on said lever for engaging said notched segment so as to hold said track in different positions of adjustment, substam tiallyas specified. I

5. The combination with a fuel-magazine,

conduit, s'uba conduit leading thereto, and a conveyor in said conduit, said conveyer having flights of var *ing carrying capacity in the length thereof, and means, substantially as described, for moving said conveyer-shaft longitudinally through said conduit and magazine so as to vary the distribution caused by the Varying carrying capacity of said conveye'r, substantially as specified.

G. The combination with a fuel-magazinc and a conduit leading thereto, a conveyer in said conduit, said c-on'veyer having'a substantiall y uniform carrying capacity through said conduit and having flights with a reduced carrying capacity within said magazine, and a movable sleeve for supporting the endof said conveyer-shaft,-and means,j

substantially as described, for adjusting said sleeve in di eren't positions to change the longitudinal osition of said shaft, substantially as specified; 7. The combination with a conveyer-shaf having conveyer-fiights of difierent' carrying capacity, a conduit in which said shaft operates, and a magazine connected to said conduit, of a screw-threaded sleeve, a supporting-bearing for said sleeve, and antifrlctlon bearing-plates in said sleeve, said sleeve being adapted to form a bearing for the front end of said shaft, substantially as specified.

'8.- The combination with a fuel-chamber, and a conduit leading thereto, said fuel-chamber being formed with inclined sides and a IOO curved bottom which forms a substantial continuation of said cond uit,a conveyerextending through said conduitand fuel-magazine and having a-substantially uniform carrying capacity in said conduit and a reduced carrying capacity in said magazine, and an angularly-arranged passage-way formed in said conduit andv leading fronrthe top thereof so as to. open into the front of' said magazine passage-way formed at the top of'said con duit of a widthlless than the diameter. of said conduit and adapted to extend into the front of said magazine, substantially as specified.

10. The combination with a fuel-magazine,

and a conduit leading horizontally into-the same, a conveyer-shaft extending through said conduit and through the bottom of said magazine, said shaft having a conveyor of sub-- stantially uniform carrying capacity through.

said conduit, and of a reduced carrying capacity within said magazine, an-angularlyings, anair-pass'age communicating with said v arr'an ged passage from the top of said conduit into the front of said magazine, and means as described for adjusting'the shaft and conveyer lengitudinaily t-hrough said conduit and magazine, substantially as specified.

11. The combination of a fuel-magazine,

and a conduit leading into the same, a contwyer-fopenings in said magazine, and an air- 7 trunk communicating With'said twyer-open conduit at an angle thereto, anda connection from said air-passage to said air-trunk, substantially as specified.

13. The combination with a magazine and a conduit leading thereto, a conveyor in said conduit, and twyer-openings in said magazine, an air-trunkcommunicating with 'said twyer-openings, and an air-passage from said trunk to the conduit, said air-passage being adapted to enter said conduit at an angle thereto and into a concave pocket formed in said conduit, substantially as specified.

14. The combination with a fuel-magazine and a conduit leading thereto, said conduit being provided with a circular concave pocket therein, twyer openings in saidmagazine, and an air-trunk communicating therewith,

v a passage from said air-trunk to said concave pocket in said" conduit, substantially as speci- In testimony whereof I have hereunto set my-hand this 21st day of October, A. D. 1895.

a ARTHUR F. BROWN.- Witnesses: I

W.- W. WAGNER, WAnREN HALL. 

